Summer officially starts June 21, but the summer sun isn’t always good for your health. Take a minute to read these safety tips before heading outside.

Cover up! Wear long-sleeved shirts, pants and wide-brimmed hats. Don’t neglect your ears and back of your neck, prime spots for skin cancer. Darker, thicker and tightly-woven clothes protect better, but be careful in the heat. You might even consider sun-protective clothing — clothes with an ultraviolet protection factor (UPF) listed on their label. The higher the value, the better.

Protect your eyes from cataracts and eye disease. Wear UV-protective sunglasses — ideally, a pair that blocks 99 to 100 percent of UV radiation. They should also be large-framed or wraparound to protect the sensitive skin around your eyes.

Sunscreen is always important. The American Cancer Society recommends a product with a sun protection factor (SPF) of at least 15. However, no sunscreen provides total protection from the sun. Apply it half an hour before going outside, and reapply every two hours — more often if swimming or sweating.

Of course, the best defense from the sun’s rays is to stay in the shade. UV rays are strongest between 10 a.m. and 4 p.m. The Environmental Protection Agency recommends following the “shadow rule”: If your shadow is shorter than you are, get out of the sun. Be wary of reflective surfaces like water and sand, which make sunburn more likely.

Finally, stay hydrated. The average adult loses 2.5 liters of water a day just from sweating and even more on a hot summer day. Drink lots of water, keep to the shade and take breaks from strenuous activity.